Optical apparatus for the reproduction of superimposed pictures

ABSTRACT

Images of two or more groups of pictures exposed onto a photosensitive record carrier in the presence of gratings are projected onto a screen by focusing all of the pictures into a focal plane which accommodates several adjustable diaphragms or analogous image selecting devices each blocking all but one image of the corresponding group. Mirrors or analogous optical deflecting components are used to project the unblocked images from the focal plane onto separate sections of a screen so that two or more images can be viewed simultaneously.

United StatesPatent Bestenreiner et al.

OPTICAL APPARATUS FOR THE REPRODUCTION OF SUPERIMPOSED PICTURESInventors: Friedrich Bestenreiner, Grunwald near Munich; Reinhold Deml,Munich; Ulrich Greis, Miesbach; Josef Pleifer, Unterhaching, all ofGermany Assignee: AGFA-Gevaert Aktiengesellschaft, Leverkusen, GermanyFiled: Oct. 6, 1969 App]. No.: 863,775

Foreign Application Priority Data Oct. 5, 1968 Germany ..P 18 01 540.2

US. Cl ..350/162 SF, 350/171, 350/273,

353/37, 353/97 Int. Cl ..G02b 27/18, G02b 27/38 Field of Search..350/162 SF Feb. 22, 1972 [56] References Cited UNITED STATES PATENTS3,314,052 4/1967 Lohmann .350/162 SF UX 3,478,661 11/1969 Heckscher......350/162 SF UX 3,546,374 12/1970 Graser, Jr. ..350/162 SF X PrimaryExaminer.lohn K. Corbin Attorney-Michael S. Striker [57] ABSTRACT Imagesof two or more groups of pictures exposed onto a photosensitive recordcarrier in the presence of gratings are projected onto a screen byfocusing all of the pictures into a focal plane which accommodatesseveral adjustable diaphragms or analogous image selecting devices eachblocking all but one image of the corresponding group. Mirrors oranalogous optical deflecting components are used to project theunblocked images from the focal plane onto separate sections of a screenso that two or more images can be viewed simultaneously.

13 Claims, 6 Drawing Figures PATENTEnraazz m2 '3, 644, O l 9 SHEET 1 BF2 PF/OF AFT INVENTOR.

FRIEDRICH BESTENREINER By REINHOLD DEML ULRICH GREIS OSEF PFEIFERPAIENTEBFEB22 I972 SHEET 2 OF 2 IN V EN TOR.

FRIEDRICH BESTENREINER BY REINHOLD DEML ULRICH GREIS JOSEF PFEIFEROPTICAL APPARATUS FOR THE REPRODUCTION OF SUPERIMPOSED PICTURESCROSS-REFERENCE TO RELATED APPLICATION The apparatus of the presentinvention constitutes an improvement over and a further development ofreproducing apparatus disclosed in the copending application Ser. No.803,676 filed on Mar. 3, 1969 by Friedrich Bestenreiner et al. andassigned to the same assignee.

BACKGROUND OF THE INVENTION The present invention relates to apparatusfor reproducing pictures, written or typed texts or analogousinformation (hereinafter called pictures) which is stored on film oranother suitable record carrier. More particularly, the inventionrelates to improvements in projectors for viewing of information whichis stored on record carriers in a manner as disclosed in the copendingapplication Ser. No. 803,676 filed Mar. 3, I969 by Bestenreiner et al.and assigned to the same assignee. Said copending application disclosesa method and apparatus for superimposing two or more pictures or otherinformation on a single record carrier by employing gratings havingdifferent grating constants and/or different azimuth angles and byresorting to higher diffraction orders. The reproducing apparatus orprojector of the aforementioned copending application is designed toreproduce the image of one of several superimposed pictures at a time.It can happen, however, that the images of two or more of the picturesstored on a common record carrier should be observable at the same time.For example, if the information stored on a developed roll film includesthe specifications and drawings of patents, it is convenient and hencedesirable to project the image of the drawing simultaneously with theprojection of image of the specification so that the descriptive partand/or the claims can be read with reference to the drawing. Theapparatus of the aforesaid copending application is incapable ofprojecting the images of more than one of several superimposed picturesat a time.

SUMMARY OF THE INVENTION An object of the present invention is toprovide a novel and improved apparatus which is designed in such a waythat it can simultaneously reproduce the images of two or more ofseveral superimposed pictures on a common record carrier.

Another object of the invention is to provide a projector which canreproduce images of several superimposed pictures in such a way that thereproductions are observable at a desired distance from each other.

A further object of the invention is to provide a projector which isespecially suited for simultaneous viewing of two or more discrete pagesof text, illustrations, charts, maps or other information stored byrepeated exposure of photographic film and by subsequent developing ofthe thus exposed film.

The invention is embodied in an apparatus for selective reproduction ofimages of several pictures which are exposed in superimposition uponeach other on a light-transmitting record carrier in the presence ofgratings having different constants or a grating placed into severalangular positions. The apparatus comprises means for focusing into apredetermined focal plane all of the images superimposed upon a selectedportion of a record carrier so that the resulting diffraction orders ofimages are separate from each other, selector means located in the focalplane and adjustable to mask or block selected diffraction orders ofimages and to render at least two of the images visible, and opticalmeans preferably located in or close to the focal plane and serving toseparately project the visible images so that the thus projected imagesare observable simultaneously, for example, on separate sections ofascreen.

The optical means may include sets of mirrors, prisms or analogouscomponents which can be fixedly mounted to insure that each selectedvisible image is projected in a preselected direction and can be seen ona preselected area of the screen.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved reproducing apparatus itself, however, both as to itsconstruction and its mode of operation, together with additionalfeatures and advantages thereof, will be best understood upon perusal ofthe following detailed description of certain specific embodiments withreference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic side elevationalview of a prior reproducing apparatus;

FIG. 2 is a schematic perspective view of a reproducing apparatus whichembodies one form of the invention;

FIG. 3 is a horizontal sectional view taken along the line III-III ofFIG. 1;

FIG. 4 is a transverse vertical sectional view as seen in the directionof arrows from the line IV-IV of FIG. 2;

FIG. 5 is an enlarged sectional view as seen in the direction of arrowsfrom the line VV of FIG. 4; and

FIG. 6 is a sectional view ofa further detail in the apparatus of FIG.2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustratesschematically a reproducing apparatus which is identical with theapparatus shown in FIG. 4 of the copending application Ser. No. 803,676.The apparatus comprises a relatively small (preferably punctiform) lightsource 2 which emits light against a record carrier 1 (developed rollfilm) through a condenser lens 3. The plane in which the light source 2is imaged by the condenser lens 3 is the so-called local frequencyplane. The carrier 1 stores information (pictures) which was appliedthereto by means of gratings having different constants or by placing agrating in different angular positions during successive exposures. Theaforementioned local frequency plane accommodates diaphragm means 4which only permits passage of such light which is needed to project oneof several pictures onto a screen 6. As fully explained in the copendingapplication Ser. No. 803,676, the light concentrations in the localfrequency plane are separated from each other in accordance with thegrating constant and/or the angular position of the grating. Theapparatus further comprises an objective lens 5 located between thediaphragm means 4 and the screen 6 and serving to project the selectedimage onto the screen. A different picture will be seen on the screen 6in response to a change in the position of the diaphragm means 4, i.e.,the apparatus of FIG. 1 can project one picture at a time or severalsuperimposed pictures at a time.

FIG. 2 illustrates a reproducing apparatus which embodies one form ofthe present invention. The record carrier 1 is a film on which severalsuperimposed images were exposed in response to displacement of agrating (carrier frequency) through angles of equal magnitude.Therefore, the light concentrations corresponding to the exposuresappear in the local frequency plane (focal plane) in the form of acircle and are angularly offset with reference to each other by anglescorresponding to those between successive angular positions of thegrating. The concentrations ofthe plus first order are confined to theupper half of the circle and the concentrations of the minus first orderare confined to the lower half of the circle. The concentrations of eachhigher diffraction order are located on a separate circle of greaterradius but at the same angular distance from each other.

One of the differences between the apparatus of FIGS. 1 and 2 is thatthe objective lens 5 is placed between a novel picture selecting device7 and the record carrier 1. The light source 2 is imaged by the lenses 3and 5 in the plane of the selecting device 7, and the objective lens 5also projects the picture or pictures onto the screen 6. The selectingdevice 7 comprises several sector-shaped vanes or blades which areturnable about the optical axis in a manner to be fully described withreference to FIGS. 4 and 5. The vanes form two groups and the vanes ofeach of these groups are movable by one of two manually operatedadjusting members 7a, 7b. There are seven light concentrations in eachof the two semicircles.

The apparatus of FIG. 2 further comprises an optical picture deflectingunit whose components are located immediate ly or closely behind theselecting device 7. Such components include two mirrors 8 and 9. Themirror 8 reflects one of the selected pictures onto a further mirror 10which reflects the picture onto the section 6a of a screen 6 located ina projection plane. The mirror 9 cooperates with a fourth mirror 11 toreflect a further picture onto the section 6b of the screen 6. As shown,the mirrors 8, l0 reflect pictures from the lower part of the localfrequency plane (device 7) and the mirrors 9, l1 reflect pictures fromthe upper part of such plane. Since the arrangement is such that thelight concentrations of the plus first order appear in one part and thelight concentrations of the minus first order appear in the other partof the local frequency plane, the user is in a position to manipulatethe adjusting members 7a, 7b and to thereby project one of severalpictures onto each of the screen sections 6a, 6b. Since the plus firstand minus first orders are totally equivalent, the brightness ofsimultaneously projected pairs of picture is the same, provided that theexposures were made under identical circumstances.

The exact positions of the mirrors 8-11 with reference to each other andwith reference to the selecting device 7 are shown in FIG. 3. It isclear that these mirrors can be replaced by prisms or other suitableoptical picture deflecting components. It is further clear that, byproperly increasing the opening ratio of the objective and by properlyselecting the grating constant, the apparatus of FIG. 2 can evaluate thesecond order of light concentrations; in such apparatus, the opticaldeflecting unit employs additional mirrors or analogous components toproject more than two discrete pictures at a time, e.g., a total of fouror six pictures each of which is observable on a different section ofthe screen. One pair of pictures can be projected for each order oflight concentrations.

In many instances, the brightness of pictures in each order of lightconcentrations is different. This can be compensated for by employinglight weakening means in the path of brighter pictures to insure thatthe brightness of pictures on the screen is at least substantiallyuniform. Alternatively, the light diffracting power of gratings whichare used in exposing of pictures onto the record carrier 1 can beselected in such a way that the diffraction orders which arecontemplated for evaluation exhibit a substantially uniform andpreferably strongly pronounced brightness. This can be achieved, forexample, by selecting a grating whose diffracting power or absorptioncurve during exposure is such that the selected orders appear withsubstantially equal amplitude. For example, a grating which is suitablefor such purposes can be produced by exposure of film withsuperimposition of corresponding harmonic local frequencies. The justmentioned method of making gratings is fully disclosed in Ser. No.803,676.

The details of one embodiment of a suitable picture selecting device foruse in the apparatus of FIG. 2 are shown in FIGS. 4 to 6. The device 7therein shown comprises a shaft 12 whose axis coincides with the opticalaxis and which supports two sets of vanes or blades including an uppergroup or set of vanes 13, I4, l5, l6, 17, 18, 19, and 21. The lowergroup or set preferably comprises an equal number of vanes. The vane 17is wider than the remaining vanes and is provided with an aperture inthe form of a radially extending elongated slot 17a for one of thediffraction orders, for example, for the minus first order. The vane 17can be turned back and forth about the axis of the shaft 12 between thetwo outermost orders whereby all of the superimposed images areprojected onto the screen in a predetermined sequence and independentlyof each other. The means for coupling the vanes 13-21 for movement witheach other but for permitting some movement of each vane with referenceto the adjoining vane or vanes comprises cooperating motion transmittingprojections or lugs, such as the lugs 14b and 15a shown in FIG. 4. Eachvane partially overlaps an adjoining vane. As shown in FIG, 5, the vane17 is attached to the shaft 12 and can be rotated by a gear 23 which isaffixed to the shaft. The gear 23 meshes with a gear 24 which isrotatable by a flexible shaft 25 and an adjusting knob 26 mounted on awall 33 of the apparatus. The number of teeth on the gear 24 is half thenumber of teeth on the gear 23. The wall 33 is preferably the front wallof the apparatus and is readily accessible to the operators hand. Theoperator is thus in position to move the vane 17 between its two endpositions and to select that picture which is to be projected throughthe slot 17a.

The lower part of FIG. 5 illustrates one of the second group or group ofvanes, namely, a vane 27 having an aperture or slot 270 andcorresponding to the vane 17 of the upper set. The vane 27 is affixed toa hollow shaft 28 which is turnable on the shaft 12 and can be rotatedby means of mating gears 29, 30. The gear 30 can be rotated by anadjusting knob 32 on the wall 33 by way of a flexible shaft 31. The slot27a of the vane 27 permits passage of the plus first order. The wall 33is preferably provided with scales (not shown) which facilitate theselection of pictures.

It is clear that the mechanical connections (shafts 25, 31 etc.) betweenthe knobs 26, 32 and the corresponding vanes 17, 27 can be replaced byelectrical or other suitable connections. It is also possible to employa set of electromagnetically operated shutters, one for each brightnessand to place such shutters into the plane of the selecting device 7. Apushbutton switch is then provided to place a shutter in operativeposition in response to adjustment of the vane 17 or 27. The justmentioned modification is of particular advantage when the recordcarrier 1 is exposed by resorting to gratings having differentconstants.

It is also within the purview of our invention to combine the selectingdevice with the optical picture deflecting unit. For example, the mirror9 of FIGS. 2 and 3 may be provided with movable strongly light-absorbentdiaphragm vanes which prevent projection of more than one picture at atime. Thus, the picture deflecting unit can be rendered adjustable sothat it can discriminate between several pictures.

The record carrier 1 used in the apparatus of FIG. 2 is preferablyexposed to light in the presence of gratings having such diffractingand/or absorbing characteristics that the brightness of pictures in eachdiffraction order is at least nearly uniform, i.e., that all ordersexhibit substantially identical intensities. Thus, a Fourrier analysisof the diffracting power or absorption of the grating should show thatthe evaluated orders appear with the same amplitude.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of our contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is:

1. Apparatus for selective reproduction of images of several pictureswhich are exposed in superimposition upon each other on a record carrierin the presence of diffraction gratings, comprising means for focusinginto a predetermined focal plane all of the images which aresuperimposed on a selected portion of a record carrier so that thediffraction orders of said images are separate from each other; selectormeans located in said plane and adjustable to mask selected ones of saiddiffraction orders of said images; and optical means located behind saidselector means and arranged to deflect the positive diffraction ordersof each image in a first direction and to deflect the negativediffraction orders of each image in a second direction which isdifferent from said first direction, said selector means having at leasttwo openings which are adjustable so that the positive diffractionorders of a first image are deflected in said first direction and thenegative diffraction orders of a second image are deflected in saidsecond direction and that the thus projected images are observablesimultaneously.

2, Apparatus as defined in claim 1, wherein said optical means comprisesa plurality of mirrors arranged to project said visible images ontoseparate sections of a projection plane.

3. Apparatus as defined in claim 1, wherein said optical means comprisesseveral groups of optical components, one for each of said visibleimages, for projecting the respective visible images into discretesections of a second plane.

4. Apparatus as defined in claim 1, wherein said selector meanscomprises a plurality of electromagnetically controlled shutters whosecharacteristics are a function of the brightness of selected visibleimages, and means for moving said shutters in said focal plane tothereby select the corresponding visible images.

5. Apparatus as defined in claim 1, wherein said selector meanscomprises adjustable diaphragm means and adjusting means for saiddiaphragm means. a

6. Apparatus as defined in claim 1, wherein said record carrier storesgroups of pictures of several diffraction orders and wherein saidselector means and said optical means comprise means for simultaneouslyselecting and projecting visible images of pictures of each of saidorders.

7. Apparatus as defined in claim 6, further comprising means fordetermining the brightness of projected images.

8. Apparatus as defined in claim 7, wherein said last-mentioned meanscomprises diaphragm means.

9. Apparatus as defined in claim 7, wherein said last-mentioned meanscomprises filter means.

10. Apparatus as defined in claim 1, wherein said carrier stores severalgroups of pictures obtained by exposure to light in the presence ofgratings having such diffracting or absorption characteristics that thebrightness of all pictures in a group is substantially the same.

11. Apparatus for selective reproduction of images of several pictureswhich are exposed in superimposition upon each other on a record carrierin the presence of diffraction gratings, comprising means for focusinginto a predetermined focal plane all of the images which aresuperimposed on a selected portion of a record carrier so that thediffraction 0rders of said images are separate from each other; selectormeans located in said plane and adjustable to mask selected ones of saiddiffraction orders of said images and to render at least two of saidimages visible, said selector means comprising adjustable diaphragmmeans and adjusting means for said diaphragm means, said diaphragm meanscomprising a plurality of groups of diaphragm vanes which are turnableabout the optical axis of said focusing means and each of said groupscomprising an apertured vane movable by said adjusting means between aplurality of positions in each of which the aperture of the respectiveapertured vane renders visible a different one of said superimposedpictures; and optical means for separately projecting said visibleimages so that the thus projected images are observable simultaneously.

12. Apparatus as defined in claim 11, wherein said diaphragm meansfurther comprises coupling means connecting the vanes of each group formovement with and relative to each otherv 13. Apparatus as defined inclaim 11, wherein said adjusting means comprises rotary knobs andflexible shafts connecting said knobs with the respective groups ofvanes.

1. Apparatus for selective reproduction of images of several pictureswhich are exposed in superimposition upon each other on a record carrierin the presence of diffraction gratings, comprising means for focusinginto a predetermined focal plane all of the images which aresuperimposed on a selected portion of a record carrier so that thediffraction orders of said images are separate from each other; selectormeans located in said plane and adjustable to mask selected ones of saiddiffraction orders of said images; and optical means located behind saidselector means and arranged to deflect the positive diffraction ordersof each image in a first direction and to deflect the negativediffraction orders of each image in a second direction which isdifferent from said first direction, said selector means having at leasttwo openings which are adjustable so that the positive diffractionorders of a first image are deflected in said first direction and thenegative diffraction orders of a second image are deflected in saidsecond direction and that the thus projected images are observablesimultaneously.
 2. Apparatus as defined in claim 1, wherein said opticalmeans comprises a plurality of mirrors arranged to project said visibleimages onto separate sections of a projection plane.
 3. Apparatus asdefined in claim 1, wherein said optical means comprises several groupsof optical components, one for each of said visible images, forprojecting the respective visible images into discrete sections of asecond plane.
 4. Apparatus as defined in claim 1, wherein said selectormeans comprises a plurality of electromagnetically controlled shutterswhose characteristics are a function of the brightness of selectedvisible images, and means for moving said shutters in said focal planeto thereby select the corresponding visible images.
 5. Apparatus asdefined in claim 1, wherein said selector means comprises adjustablediaphragm means and adjusting means for said diaphragm means. 6.Apparatus as defined in claim 1, wherein said record carrier storesgroups of pictures of several diffraction orders and wherein saidselector means and said optical means comprise means for simultaneouslyselecting and projecting visible images of pictures of each of saidorders.
 7. Apparatus as defined in claim 6, further comprising means fordetermining the brightness of projected images.
 8. Apparatus as definedin claim 7, wherein said last-mentioned means comprises diaphragm means.9. Apparatus as defined in claim 7, wherein said last-mentioned meanscomprises filter means.
 10. Apparatus as defined in claim 1, whereinsaid carrier stores several groups of pictures obtained by exposure tolight in the presence of gratings having such diffracting or absorptioncharacteristics that the brightness of all pictures in a group issubstantially the same.
 11. Apparatus for selective reproduction ofimages of several pictures which are exposed in superimposition uponeach other on a record carrier in the presence of diffractiOn gratings,comprising means for focusing into a predetermined focal plane all ofthe images which are superimposed on a selected portion of a recordcarrier so that the diffraction orders of said images are separate fromeach other; selector means located in said plane and adjustable to maskselected ones of said diffraction orders of said images and to render atleast two of said images visible, said selector means comprisingadjustable diaphragm means and adjusting means for said diaphragm means,said diaphragm means comprising a plurality of groups of diaphragm vaneswhich are turnable about the optical axis of said focusing means andeach of said groups comprising an apertured vane movable by saidadjusting means between a plurality of positions in each of which theaperture of the respective apertured vane renders visible a differentone of said superimposed pictures; and optical means for separatelyprojecting said visible images so that the thus projected images areobservable simultaneously.
 12. Apparatus as defined in claim 11, whereinsaid diaphragm means further comprises coupling means connecting thevanes of each group for movement with and relative to each other. 13.Apparatus as defined in claim 11, wherein said adjusting means comprisesrotary knobs and flexible shafts connecting said knobs with therespective groups of vanes.